Chert is a rock that has the same or similar elemental composition to quartz. Thus, conventional logging tools that measure density, neutron, and resistivity may only identify chert as quartz across a subterranean formation rather than chert, itself. Chert, however, relative to many other rocks in hydrocarbon bearing formations, has a high rock strength, and the presence of chert in subterranean formations may add difficulties to drilling and completion operations.